xstar

N-body simulator

Version : 2.2
Author(s) : Wayne Schlitt, (wayne@midwestcs.com)
License : GPL
Website : http://www.midwestcs.com/xstar/

Installs from Open Source Astronomy for Win32/Cygwin cd 3
Disk space required for installation is 35.18 Mb

After the package is installed it can be accessed using the command


		/opt/astro/bin/startxstar

     

A shortcut will be installed in the KDE/GNOME desktop menu system,
as an entry in the Astronomy submenu

Screenshots

Summary

This program solves the n-body problem, and displays the results on the screen. It starts by putting a bunch of stars on the screen, and then it lets the inter-body gravitational forces move the stars around. The result is a lot of neat wandering paths, as the stars interact and collide.

XStar can be used to animate the root window, as a screen saver or just to display stuff in a regular window.

The XStar N-body Solver

XStar is a Unix program that simulates the movement of stars. It starts by putting a bunch of stars on the screen, and then it lets the inter-body gravitational forces move the stars around. The result is a lot of neat wandering paths, as the stars interact and collide.

Figuring out what paths these stars should take is called the "N-Body Problem", and when there are more than 3 stars involved (N>3), this can be a very hard problem to solve. XStar is just a "toy" N-body solver, but it generates a lot of pretty pictures and gives you an idea of how stars interact. "Real" N-body solvers have to work with many thousands, or even millions of stars, while XStar works with dozens.

Along with the program, there is a fairly large document that explains the N-Body problem in a fair amount of detail. It doesn't get into the gory details of the "real" N-body solvers, but it does give you an overview of the techniques they use.

All comments, bug reports, bug fixes, enhancements, etc are welcome. Send them to me at wayne@midwestcs.com.

This program is really a heavily modified version of XGrav, which was written by David Flater (dave@case50.ncsl.nist.gov) and posted to alt.sources on 1/21/95. I liked the program enough that I was really interested in it, but I didn't like it enough to leave it alone. The idea was Dave's, but I don't think too much of his code has been left unchanged. There is probably more untouched code from XSwarm, which Dave used to implement the X port of his n-body problem solving code.